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Old 12-03-2019, 09:36   #61
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Re: Mantus rode

Quote:
Originally Posted by ramblinrod View Post
Yup. And if one is in a harbour with wind coming in the mouth, they are going to be on a lee shore (unless they head out to sea, which could be the wisest choice yet). . .

A lee shore is never the place to choose, to be anchored in a storm, no matter what kind of bottom, slope, etc. you have. The fundamental issue in surviving storms is shelter. If the wind is coming in the mouth, and it's a storm, the only thing to do is immediately get out of there. That's really basic stuff.
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Old 12-03-2019, 09:45   #62
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Re: Mantus rode

Quote:
Originally Posted by ramblinrod View Post
I'm sorry, but I am just not impressed by what one has done, or who they listen to, when they recommend anchoring with shorter scope when longer scope is possible, everything else being equal.

HAHAHAHA, I can only imagine what anchorages would look like if everyone, always used a 10 to 1 scope. DH has a ton more experience anchoring in deep water then most folks here. In reality it would be physically impossible to carry enough chain to anchor 10 to 1 in 100 feet feet depth. Not with the typical cruising yacht. Nor is it needed.

Myself I have many many thousands of nights anchoring in shallow water. That is less then 25 feet. Only once or twice did I anchor with longer the 5 to 1 scope. And this with a poor holding Bruce anchor. Most of the time, I'm using 3 to 1 scope and let out to 5 or 6 to 1 if a storm is a calling.

With the more modern anchor, 5 or 6 to 1 scope is more then adequate in all but major storm conditions. While ultimate holding does get slightly better extending from 6 to 1 to 10 to 1, it's probably not sufficient in 99.9% of cases.

Why. Because regardless of scope, one has to consider the ultimate holding capacity of the bottom soil. All anchors drag. But with the modern anchors, it's more due to soil conditions then the anchor design.

In storm conditions, the soil holding will most liking fail first when using a modern anchor.


BTW Rod, just because someone disagrees with you does not make it insulting. Good Lord, it's the internet and everyone disagrees with each other.

I'll take someones experience over what an author wrote 40-50 years ago about anchoring. If we were all anchoring with danforth's, northhills and luke anchors, 10 to 1 might make sense.

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Old 12-03-2019, 09:46   #63
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Re: Mantus rode

Steve Dashew, in his new 83' boat, writing just a couple of weeks ago from Antarctica:


"At 0500, the wind came up to the mid 40s with gusts to 65 knots. By 0800, it became obvious that our anchorage was untenable as the wind was projected to shift southerly which would put us on a lee shore and we were already in only 5.5 meters of water.
"Reluctantly, we chose to up anchor and move out into the middle of the bay in 35 meters of water with 120 meters of chain out. Even though the fetch was limited, waves in the bay were up to 2 meters. All this made worse by the fact that ice was blowing both down the bay and into our former anchorage. We are currently doing ice watch with the engines running and, while still anchored, using the engines to negotiate around the bergs as they come down the bay.

https://setsail.com/no-good-choices-...ce/#more-47538


Yet another bad seaman! Choosing to anchor in the middle of the bay in a storm with gusts in the 60's! With 3.4:1 scope. Instead of moving over to the lee shore in shallower water where he could get more scope. Somebody needs to let him know that this is dangerous.
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Old 12-03-2019, 11:09   #64
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Re: Mantus rode

Quote:
Originally Posted by ramblinrod View Post
I'm sorry, but I am just not impressed by what one has done, or who they listen to, when they recommend anchoring with shorter scope when longer scope is possible, everything else being equal.. .

A fundamental problem in this discussion, is that no one ever said that. Everything else being equal, of course you go for more scope. Scope is good, of course, up to the point of vanishing returns (at most 8:1).


You seem to have failed to understand that all of the problems presented were not easy choices of more or less scope, everything else being equal. Everything wasn't equal. There was a sloping bottom with notably poor holding on the rocky, sloping part (not unusual). There were doubts about doing a shore tie (including not having anything to tie to).


So you have to compromise somewhere, where do you do it? What is the best decision? This is a life and death decision, because there are no rescue services there and the water is +1C. This is not an armchair theoretical exercise.


So here you will simply fail to be able to make a decision, if you don't understand how your particular anchor and your particular chain perform at different scopes and in different depths. If you follow a lazy, oversimplified rule like "anything less than 8:1 is compromising holding", then you are not equipped with the knowledge you need to make that decision.


So here you really must know things like -- you need less scope in greater depth (4.25:1 equals 6:1 when going from 20' of water to 40' in one calculated example in Peter Smith's article -- https://www.petersmith.net.nz/boat-anchors/catenary.php), and required scope roughly halves at 100' of water, depending on the forces and weight of the chain of course.



Lacking this knowledge, could cost your life, in a situation like I was in last summer. Do you bug out and head out into the flying ice? Or do you take a chance on an excellent flat spot of dense silt in the middle of the bay, even if you can only get 2.33:1 scope on it? If you know enough about all this stuff, and you have enough experience, you know that a 100 pound Spade attached to 700 pounds of chain will in fact hold well under those conditions, despite the short scope (which is roughly equivalent to 4.7:1 in shallower water -- another fact, the knowing of which might save your life) and that you should clearly go for the good holding in deep water.



If all you know is "anything less than 8:1 compromises holding", then you won't understand the choices you have, so you will be out in a storm in the icebergs and flying growlers.


You need to know this stuff also to choose anchoring spots in general. Do you take the one with iffy holding but more room allowing more scope, or do you take the one with a perfect bottom but it's deeper or there are obstacles, so you will have to use a shorter scope?



Well, the difference between medium holding and good holding is about 3x. The difference between 8:1 scope and 6:1 scope is negligible under most conditions even in shallow water; 5:1 will generally give you maximum holding in deep water if you are on heavy chain. So you gain 3x of holding force by going from 8:1 in shallow water and medium holding to 5:1 in deep water and good holding -- a smart move, if you have the knowledge to perceive it.


As simple as possible, but not simpler.
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Old 12-03-2019, 11:22   #65
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Re: Mantus rode

Quote:
Originally Posted by Dockhead View Post
The situation was this – back of Scorseby Sund...
Thanks for the great story of real-world anchoring in a *VERY* challenging situation.

Quote:
Originally Posted by Dockhead View Post
Sloping bottoms are nothing but bad news, very bad news
I learned this the hard way ... I arrived in a good anchorage in Alaska ahead of some forecast strong wind. The anchorage had acres of space with a beautiful flat bottom at 25m depth ... but with no windlass hauling in 25m of chain and anchor although possible, is hard, and I'm lazy ... so I looked around along the weather shore and found a place I could anchor in 10m where the shore sloped up and I put out 5:1 chain.

The anchor held fine for half the night, but eventually the wind got too strong, and the anchor pulled out and dragged ... so in the middle of the night I dragged back over the good bottom at 25m. Although definitely more exposed without the shelter from the trees along the shoreline, and extended to only 4:1 mixed rope/chain scope, it held fast the rest of the night despite having not yet seen the worst of the wind ... shoulda anchored there in the first place and avoided the 2am drama ... lesson learned, only myself to blame.
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Old 12-03-2019, 12:30   #66
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Re: Mantus rode

[QUOTE=sailorchic34;2846125]
Quote:
HAHAHAHA, I can only imagine what anchorages would look like if everyone, always used a 10 to 1 scope.
Hey sailor chic, nobody here, especially I, suggested everyone always use 10:1, especially where it isn't practical.

Hmmm, kind of insulting.

I think the valid point I have made here is, that for storm conditions, where 10:1 can be used, it is wise to, as opposed to 3:1, or anything in between.

Why?

Because everything else equal longer scope is better, and in general, one should use the resources available to stay safe in a storm.

I can't believe anyone with any level of sailing experience, is arguing against this.

Quote:
In reality it would be physically impossible to carry enough chain to anchor 10 to 1 in 100 feet feet depth. Not with the typical cruising yacht.
Quite frankly, I have never suggested that anyone carry 1000 ft of chain.

That was just another cheap shot / misleading statement by another poster.

As you clearly stated, one would rarely seek out a 100 ft deep anchorage, where suitable shallower anchorages were available.

Why?

They aren't likely to have enough rode to put out 10:1 if they need it.

If they only have 300 ft, of course they can only put out 3:1.

This by no means makes 3:1 in a deep anchorage better than 10:1 in a shallow one, everything else being equal.

Lastly, how much rode can be carried and what configuration is best is determined by the boat design, configuration, and user needs and wants, as I clearly stated, in my first post to this thread.

If I had a choice of three anchorages, everything else equal, and one enabled 3:1 scope, another 6:1 scope, and the last 10:1 scope, I know which anchorage I would pick to weather a pending storm.

No question; the last one would be better.

(Now if anyone wants to contrive unevenly applied circumstances that favour a less favourable situation, well that's a silly game anyone can play, to attempt to claim there is no value to general rules.)

That is just pure bovine excrement in my opinion.

Quote:
Myself I have many many thousands of nights anchoring in shallow water. That is less then 25 feet. Only once or twice did I anchor with longer the 5 to 1 scope. And this with a poor holding Bruce anchor. Most of the time, I'm using 3 to 1 scope and let out to 5 or 6 to 1 if a storm is a calling.
So this supports my point; you have determined that 3:1 is less desirable, and longer scope is desirable, for storm conditions.

I agree.

It's exactly what I am saying.

I have also anchored a lot, and based on my experience, despite dragging only twice (of any consequence), for storm conditions, I look for an anchorage with good holding, excellent protection from the wind, and where I can deploy as much scope as possible (while remaining in the wind protection). I will most certainly not, look to anchor in the middle of a 100 ft deep bay, if I can possibly avoid it.

Why?

I would have to add on to my normal rode to get up to 10:1 scope out.

Quote:
While ultimate holding does get slightly better extending from 6 to 1 to 10 to 1...
Thank you! I finally hold out some hope for the sensibility of the forum.

Quote:
BTW Rod, just because someone disagrees with you does not make it insulting. Good Lord, it's the internet and everyone disagrees with each other.
Oh, I agree 100%.

As I've stated, I don't mind at all if someone disagrees with me.

It is only when they are trying to insult me with snide back-handed remarks, that I object to

Quote:
I'll take someone's experience over what an author wrote 40-50 years ago about anchoring.
Absolutely!

And the experience I trust most, IS MY OWN.

When that is supported by everything I've read, I trust it even more.

If someone on the internet suggests something to contradict it, supported with little evidence other than claiming that they have managed to get away with it on occasion, or that someone else has published something that declares it is possible, I still trust my own experience, supported by the experts I trust, far more.

Quote:
If we were all anchoring with danforth's, northhills and luke anchors, 10 to 1 might make sense.
My position is that EVERY ANCHOR holds better with more scope.

Interestingly, it is my opinion, that in certain conditions, the holding power of a Danforth, can be hard to beat.

Anyway, thank you for your contradictory but non-insulting comments (well mostly, the first sentence was borderline). Quite refreshing indeed.
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Old 12-03-2019, 15:46   #67
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Re: Mantus rode

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Originally Posted by Dockhead View Post
You seem to have failed to understand that all of the problems presented were not easy choices of more or less scope,
I'm sorry, but it I don't believe I have failed anything.

I recommended that folks carry lots of rode.

You claimed that they only need carry enough for 3:1 scope where they intend to anchor in storms.

I believe this is incorrect and have stated my reason why.

You have restated your belief with supposed examples (mostly unrelated to your point btw) which have not convinced me that your position is valid, so I have not changed my position on the value of scope.

I don't believe the discussion need go any further.

You go ahead and use your 3:1 scope and I will continue to use 10:1 for storm conditions.

For others, I don't believe one can really err where there is room to put out more scope, but I surely believe one can err by not putting out enough where they can.

If someone chooses an anchorage where they can only put out 3:1, where they could have put out more, and they drag, who's fault is it gonna be? certainly not mine, and definitely not Dockhead, it will be the fault of the owner, not the wind, not the anchor, not the bottom, not the weather forecast; but the one who decided to short scope the anchor when they could have used more.
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Old 12-03-2019, 19:50   #68
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Re: Mantus rode

Quote:
Originally Posted by RR
Rule 6: Total rode length. For the standard rode, this needs to be at least 10 times the maximum depth + bow height, you ever expect to anchor in.
Rod how much rode do you carry on your boat?

Quote:
Originally Posted by Dockhead
Required scope varies a lot according to size and quality of the anchor and depth of the water.
No specifying 3:1 there.

Quote:
Originally Posted by Dockhead
A sailor who fails to appreciate that the amount of anchor chain required on board, and the amount of scope needed, varies according to a number of factors, and is less in deeper water, will make bad decisions if he is faced with a choice of anchoring on 4:1 on a perfectly good bottom in deep water, or going out to sea in a storm or moving to an anchorage with rocks and a crappy bottom but shallow enough so that he can use 8:1.
Not here either... looks like good advise to me

Quote:
Originally Posted by Dockhead
4. Use the right scope, not the most scope. 5:1 or 6:1 is almost always enough if you have a good anchor and use decent technique, less in deeper water.
Same here.

Quote:
Originally Posted by RR
I believe that your advice here, to use little scope 3:1, instead of lots of scope 10:1, for storm conditions, is the ABSOLUTE WORST AND MOST DANGEROUS ADVICE I have ever read on CF.
Ah, here it is. Rod believes DH advised 3:1. I see that Rod did not understand the place and the conditions. Cognitive dissonance I suspect.

Quote:
Originally Posted by RR
If anchoring in a small harbour with a sloping bottom and a storm coming, it is best to set the anchor on the ascending slope, on the opposite side the wind is to come from, at a depth that gives 10:1 scope (or as close as practical).

For example, if the storm is coming from the north, you have 300 ft of rode and the best nearby harbour is 100 ft deep in the centre, mud bottom, DO NOT ANCHOR IN THE CENTRE IN 100 ft WITH 3:1 SCOPE.

Instead, set the anchor in 30 ft of water on the south ascending slope and use a 10:1 scope.
Classic Rod comment. Skip the details and create a false comparison. Toss in Mud too!

OK, whats wrong with this picture? Well, how about put yourself on a lee shore. Oh don't forget that you are at the point of maximum fetch pushing you to the lee shore.

And not for those of you who do not do math.

Anchored in 30' of water with 10:1 scope requires a minimum bottom slope angle of 5.7 degrees. The boat will be 298' from the anchor. With that bottom slope a boat with 6' of draft will be grounding (ignoring wave action) when it is 61' from shore. So the anchor will need to be more than (61' + 298') 359' from shore or else it will be grounded and pounding.

Switch to a 45 degree slope angle and try for a 10:1 scope. If you anchor is in 30 ' of water at 45 degrees then you are 30' from shore. So for 10:1 scope (300' of rode) while in 30' of water and 45 degree slope angle you will be (300 - sqrt(30&2+30^2) ) 258 feet up the bank.

Please, do the GD math before making crazy statements. It is clear that you have no understanding of what is being talked about.

Quote:
Originally Posted by RR
As in this thread, I post information that I believe may help forum members.

When contradicted or challenged by others, I support my position based on my knowledge, skill, and ability, with facts, logic, and reasoning.
Simply hubris. Belief and book learning is no (say what year were those books published) substitute for experience and knowledge.

Quote:
Originally Posted by RR
I'm sorry, but I am just not impressed by what one has done, or who they listen to, when they recommend anchoring with shorter scope when longer scope is possible, everything else being equal.
Qualify, qualify, qualify. Try backtracking and present your accomplishments and Bona fides before casting doubt on others. You by far IMO have the least trustworthy opinion in this thread. I take your opinion not with a grain of salt but with a salt lick of salt.
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Old 12-03-2019, 19:53   #69
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Re: Mantus rode

Quote:
Originally Posted by ramblinrod View Post
I'm sorry, but it I don't believe I have failed anything.

I recommended that folks carry lots of rode.

You claimed that they only need carry enough for 3:1 scope where they intend to anchor in storms.

I believe this is incorrect and have stated my reason why.

You have restated your belief with supposed examples (mostly unrelated to your point btw) which have not convinced me that your position is valid, so I have not changed my position on the value of scope.

I don't believe the discussion need go any further.

You go ahead and use your 3:1 scope and I will continue to use 10:1 for storm conditions.

For others, I don't believe one can really err where there is room to put out more scope, but I surely believe one can err by not putting out enough where they can.

If someone chooses an anchorage where they can only put out 3:1, where they could have put out more, and they drag, who's fault is it gonna be? certainly not mine, and definitely not Dockhead, it will be the fault of the owner, not the wind, not the anchor, not the bottom, not the weather forecast; but the one who decided to short scope the anchor when they could have used more.

This post is simply not accurate.

Rod, you have never ever anchored out with a 10:1 scope. You have never been anywhere near where Dockhead anchors out. And you would be better served if you had a healthy respect for your limited experience and knowledge.
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Old 12-03-2019, 20:15   #70
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Re: Mantus rode

I have learned a bunch from the discussion of high latitude anchoring and am grateful to learn from people who not only have more experience than I do but who have clearly thought it our and researched it.

My experience in anchoring in fjords is limited to parts of the British Columbia coast. It is common there for the stern of the boat to be in 200' or 300' of water when the bow is touching the cliffs. Anchoring is really only possible in the alluvial fans from the waterfalls where you drop the anchor in 200' and stern tie to trees or rings on shore. I was always uncomfortable with this for obvious reasons.

Very early on I once ran parallel to the shore at high tide looking for a place to drop the anchor in shallower water along the fan from Chatterbox falls. I was very lucky. We went past a 20' by 20' block of rock that was covered by 4' or 5' of water. I nearly Pirates of Penzance and got out of there and asked for some local advise.

When the tide went out it appeared that the block was a 20' cube of rock. Luck was on my side and this became experience rather than disaster.

Again, I thank Dockhead and the others who bring clarity and reason to this thread.
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Old 13-03-2019, 04:52   #71
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Re: Mantus rode

Quote:
Originally Posted by ramblinrod View Post
I'm sorry, but it I don't believe I have failed anything.

I recommended that folks carry lots of rode.

You claimed that they only need carry enough for 3:1 scope where they intend to anchor in storms.

I believe this is incorrect and have stated my reason why.

You have restated your belief with supposed examples (mostly unrelated to your point btw) which have not convinced me that your position is valid, so I have not changed my position on the value of scope.

I don't believe the discussion need go any further.

You go ahead and use your 3:1 scope and I will continue to use 10:1 for storm conditions.

For others, I don't believe one can really err where there is room to put out more scope, but I surely believe one can err by not putting out enough where they can.

If someone chooses an anchorage where they can only put out 3:1, where they could have put out more, and they drag, who's fault is it gonna be? certainly not mine, and definitely not Dockhead, it will be the fault of the owner, not the wind, not the anchor, not the bottom, not the weather forecast; but the one who decided to short scope the anchor when they could have used more.

All this reflects a complete lack of comprehension of what I was writing about, and the insistent attempt to impose simple solutions on complex situations which are not capable of being solved with simple solutions.


I am responding to this only to prevent any possible confusion in others:


1. Of course, NO ONE suggested anchoring on 3:1 scope anywhere, IF you have the choice to use more scope. Obviously not. More scope is good for holding, up to the point of vanishing returns (as I said many times), and too little scope (an amount which varies according to the size and type of anchor, type of rode, bottom, conditions, and water depth) will mean that your anchor won't hold.



2. However, there are many situations where it is not possible to use an ideal amount of scope. THEREFORE, it is not enough to know just one simple dumb thing ("less than 8:1 impairs holding"). It is essential to understand what is possible with your own particular ground tackle, in every particularly situation and water depth, on less scope than that. Otherwise, the first time you encounter a case where you need to anchor and you can't achieve your magic 8:1 for whatever reason, you won't know what to do. Which means you are screwed. Maybe even killed. You are not really fit to be in charge of a vessel if you don't know the MINIMUM scope you can get away with, in various situations, in case you need to.



3. Carrying "lots of rode" is great, and solves lots of problems. However, carrying lots of rode is not a simple solution to every anchoring problem. There are limits to how much rode you can use, because of swinging room. Hardly anyone carries more than 100 meters for this reason -- 100 meters of rode produces a one-cable -- a one-tenth of a mile -- swinging circle. If you use heavy chain, there are also limitations on how much rode you can carry.





That's all I was saying. In short, anchoring is an art, which requires more knowledge than just memorizing a couple of oversimplified "rules".




And yes, there are some narrow situations where you can weather a storm on 3:1 scope, as I have many times, as has Dashew and Morgan's Cloud and probably everyone who has cruised challenging high latitudes. That should not be interpreted to mean "just use 3:1; it's enough" -- that's not what I said.
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We must have a turn together . . . . I undress . . . . hurry me out of sight of the land,
Cushion me soft . . . . rock me in billowy drowse,
Dash me with amorous wet . . . . I can repay you."
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Old 13-03-2019, 05:14   #72
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Re: Mantus rode

Quote:
Originally Posted by evm1024 View Post
. . . My experience in anchoring in fjords is limited to parts of the British Columbia coast. It is common there for the stern of the boat to be in 200' or 300' of water when the bow is touching the cliffs. Anchoring is really only possible in the alluvial fans from the waterfalls where you drop the anchor in 200' and stern tie to trees or rings on shore. I was always uncomfortable with this for obvious reasons.. .

Greenland is like that, so you will appreciate the extreme challenges involved in anchoring there. Our whole problem was that most of the coast is so steep that you sometimes literally had one boatlength from coming on soundings to being ashore -- no possible way to anchor in that, especially without charts, so you have no idea if you are about to go onto a rock (with no one for 500 miles to pull you off). So yes, we also were always looking for "alluvial fans", and that was generally what we used. We learned to look for "shelves" where the river silt would settle and form a flat area -- that was the best chance of getting good holding at a feasible depth at a comfortable distance from shore.


Here is one such "shelf", seen from a drone:


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We must have a turn together . . . . I undress . . . . hurry me out of sight of the land,
Cushion me soft . . . . rock me in billowy drowse,
Dash me with amorous wet . . . . I can repay you."
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Old 13-03-2019, 06:29   #73
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Re: Mantus rode

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Originally Posted by ramblinrod View Post
I recommended that folks carry lots of rode.

You claimed that they only need carry enough for 3:1 scope where they intend to anchor in storms.
The most obvious type of libel/slander is to assert that someone said something they most definitely did not in order to make them look stupid, and DH never claimed what you state above. He simply said what cruisers with actual experience, rather than a well worn copy of Royce's on their desks, can attest to - with a proper anchor, chain and technique, 3:1 scope is just fine about 99.5% of the time, with the .5% handled as need be. In other words, you've either lost your reading glasses and can be forgiven because you're clueless what people are writing, or are lying to make a point no one with practical experience thinks makes sense.t

Really Rod, for someone who seems to so desperately want to be taken seriously, your opinions and way of making your points only leads to the exact opposite, which is why people with year's of experience think half of what you write is complete rubbish.
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Old 13-03-2019, 07:03   #74
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Re: Mantus rode

Quote:
Originally Posted by evm1024 View Post
Rod how much rode do you carry on your boat?



No specifying 3:1 there.



Not here either... looks like good advise to me



Same here.



Ah, here it is. Rod believes DH advised 3:1. I see that Rod did not understand the place and the conditions. Cognitive dissonance I suspect.



Classic Rod comment. Skip the details and create a false comparison. Toss in Mud too!

OK, whats wrong with this picture? Well, how about put yourself on a lee shore. Oh don't forget that you are at the point of maximum fetch pushing you to the lee shore.

And not for those of you who do not do math.

Anchored in 30' of water with 10:1 scope requires a minimum bottom slope angle of 5.7 degrees. The boat will be 298' from the anchor. With that bottom slope a boat with 6' of draft will be grounding (ignoring wave action) when it is 61' from shore. So the anchor will need to be more than (61' + 298') 359' from shore or else it will be grounded and pounding.

Switch to a 45 degree slope angle and try for a 10:1 scope. If you anchor is in 30 ' of water at 45 degrees then you are 30' from shore. So for 10:1 scope (300' of rode) while in 30' of water and 45 degree slope angle you will be (300 - sqrt(30&2+30^2) ) 258 feet up the bank.

Please, do the GD math before making crazy statements. It is clear that you have no understanding of what is being talked about.



Simply hubris. Belief and book learning is no (say what year were those books published) substitute for experience and knowledge.



Qualify, qualify, qualify. Try backtracking and present your accomplishments and Bona fides before casting doubt on others. You by far IMO have the least trustworthy opinion in this thread. I take your opinion not with a grain of salt but with a salt lick of salt.
Don't have time to respond to your comments, but I declare them invalid.
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Old 13-03-2019, 07:37   #75
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Join Date: Jan 2012
Location: Lake Ontario
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Posts: 3,250
Re: Mantus rode

Quote:
Originally Posted by Dockhead View Post
All this reflects a complete lack of comprehension of what I was writing about, and the insistent attempt to impose simple solutions on complex situations which are not capable of being solved with simple solutions.


I am responding to this only to prevent any possible confusion in others:


1. Of course, NO ONE suggested anchoring on 3:1 scope anywhere, IF you have the choice to use more scope. Obviously not. More scope is good for holding, up to the point of vanishing returns (as I said many times), and too little scope (an amount which varies according to the size and type of anchor, type of rode, bottom, conditions, and water depth) will mean that your anchor won't hold.



2. However, there are many situations where it is not possible to use an ideal amount of scope. THEREFORE, it is not enough to know just one simple dumb thing ("less than 8:1 impairs holding"). It is essential to understand what is possible with your own particular ground tackle, in every particularly situation and water depth, on less scope than that. Otherwise, the first time you encounter a case where you need to anchor and you can't achieve your magic 8:1 for whatever reason, you won't know what to do. Which means you are screwed. Maybe even killed. You are not really fit to be in charge of a vessel if you don't know the MINIMUM scope you can get away with, in various situations, in case you need to.



3. Carrying "lots of rode" is great, and solves lots of problems. However, carrying lots of rode is not a simple solution to every anchoring problem. There are limits to how much rode you can use, because of swinging room. Hardly anyone carries more than 100 meters for this reason -- 100 meters of rode produces a one-cable -- a one-tenth of a mile -- swinging circle. If you use heavy chain, there are also limitations on how much rode you can carry.





That's all I was saying. In short, anchoring is an art, which requires more knowledge than just memorizing a couple of oversimplified "rules".




And yes, there are some narrow situations where you can weather a storm on 3:1 scope, as I have many times, as has Dashew and Morgan's Cloud and probably everyone who has cruised challenging high latitudes. That should not be interpreted to mean "just use 3:1; it's enough" -- that's not what I said.
The impression I received from your posts, is that when I was recommending 10:1 scope for storm conditions, you were contradicting this and attempting to justify and even recommend using much less, including down to 3:1.

If you meant something different, I think you need to be much clearer, especially when you could be endangering people's lives, who may follow advice.

Let me make sure my position on this subject is abundantly clear...

1. "The force required to pull the catenary from chain, increases proportionally with scope."

2. "The greater the catenary, the more horizontal the force on the anchor is to the seabed."

3. "The more horizontal the force on the anchor, the greater the holding power, and the less likely the dragging."

4. "Therefore 10:1 scope is vastly superior to 3:1 scope, in all cases, everything else being equal."

Please make your position on these statements as clear, and uncomplicated as possible, to ensure there is no chance of misunderstanding, and post if you agree with these 4 principles.

A simple "Yes" or "No" will do.
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